A map of the approximate main migratory
barrenground
caribou range in northern Canada

During July each year, barrenground caribou cows of the major Canadian herds migrate north to their respective calving grounds, and then south again with their new borne calves to intercept the bulls near the tree-line. During this period the cows & calves will swell into what is known as 'bunches' - often at water crossings - and then dissipate again. This cycle continues over a two to three week period. Once the bull caribou are met, the animals spread out and graze in small groups in the late summer and early autumn migratory lull, while they feed and build up fat stores to endure the upcoming winter and mating period. The autumn period is the best time to view caribou as they are relaxed and easier to approach.

The drop of both barrenland and woodland caribou populations of the Canadian caribou herds has been a growing and alarming issue over the past decade. However, according to biologists recent indicators are now showing that some of the herds are slowly growing in numbers, while other herds continue to reduce in size.